HTML formatting

In particular, here are a couple of basic guidelines from that style guide,
which generally apply to other documentation source files, too (YAML, Markdown,
etc.):

Don't use tabs to indent text; use spaces only. Different text
editors interpret tabs differently, and some Markdown features expect spaces
and not tabs.

Indent by 2 spaces per indentation level.

Use all-lowercase for elements and attributes.

Don't leave trailing spaces at the end of a line. (Except as
needed for Markdown.)

Line length

Break lines at 80 characters except in the following cases:

The metadata tags at the top of files (such as page.metaDescription)
have to be all on one line, so those lines can be as long as needed.

If a URL in a link has a line break, the link won't work.
If a URL is longer than 80 characters (quite common), you're stuck with it. In that case,
put the URL on its own line with the href attribute to make it
easier to review the text before and after,
as the following example shows:

You can find more information in <a
href="https://example.com/long-url/johan-gambolputty-de-von-ausfern-…-von-hautkopf-of-ulm.html"
class="external-link">his biography.</a>

Break code snippets (in <pre> blocks) at 80 characters.

Note: Older files may use different line lengths.
If you're making small changes to a file that has a consistent line length other
than 80 characters, then make your changes conform to that file's line length
rather than reformatting the whole file.Note: When adding line breaks, make sure
you don't change the meaning of the code! If you're not familiar with the
programming language, ask for help from someone who is. But sometimes you
just can't avoid a long line.